Analysis of Elderly In-Migrants In Tennessee

The idea of elderly in-migrants as an important factor or stimulus to local economic development (Serow, 2001) has been confirmed by quite a few studies such as Bennett (1993); Carlson, Junk, Fox, Rudzitis, & Cann (1998); Day & Barlett (2000); Hodge (1991); Serow & Haas (1992); and Stallmann, Deller, & Shields (1999). Large-scale elderly in-migrants can bring several benefits to local economy. First, they can increase property and sales taxes, counties' largest source of revenues, without directly increasing their greatest expense such as public education; also, in-migrant retirees as a large portion of elderly do not compete for jobs so that most of counties consider them as net economic assets (Day & Barlett, 2000; Glasgow, 1991; Graff & Wiseman, 1990; Rowles & Watkins, 1993; Schneider & Green, 1992). Second, large-scale elderly in-migrants can increase local sales and capital pool through investments and savings (Campbell, 2005). Third, they can stimulate job creation and service development (Campbell, 2005). Thus, more and more counties are competing for elderly in-migrants as a source of local economic development. The question of what factors attract elderly in-migrants has been put forwarded by county governors who need to make good strategies or policies to pull them in. However, most previous studies on analyzing those factors of elderly in-migrants have been focused from macro levels such as national perspective, southern US, or state level. Little research has been conducted from a micro level of counties which are increasingly competing for elderly in-migrants with each other. The objective of this study is to determine the factors to attract elderly in-migrants from the perspective of counties in Tennessee. The main contribution of this study is to find out the county characteristics in Tennessee that attract elderly in-migrants and then provide policy implications for county governors on how to pull them in. Literatures such as Serow et al (1996 and 2001), Longino (1995), Newbold (1996), Campbell (2005), Gabriel and Rosenthal (2000) provide intuition and background for empirical models used to do the regression analysis in this paper. According to these studies, the factors of elderly in-migrants, in terms of county characteristics, include economic and non economic aspects such as income, employment, taxes, education, safety/crime rates, population (or population density), and elderly population rate. Based on these factors, the following empirical models are set up to do the regression analysis. A linear fixed-effect model is the conceptual model for this paper, instead of random effect model, because only individuals of the sample obtained are focused on and inferences are drawn restricted to these individuals within the sample (Baltagi, 2005). In other words, the linear fixed-effect model is an appropriate specification for this paper because the sample selected in this paper includes all the counties in Tennessee so that the sample is not randomly selected. Also, only those counties in Tennessee are focused on, and inferences are drawn restricted to those counties in Tennessee. Furthermore, Hausman tests are conducted in the next section to confirm that fixed-effect models should be used instead of random effect models (Baltagi, 2005). Two groups of linear fixed-effect empirical models are used to do the regression analysis. The dependent variable for the first group is in migration rate (per 100 persons) of the 60-plus cohort, which is interpreted as a percentage; and the dependent variable for the second group is in migration rate (per 100 persons) of the 67-plus cohort, which is interpreted as a percentage. The independent variables for the two groups include percentage of people with 65-plus over the whole population, percentage share of police expenditure over total expenditure, percentage share of highway expenditure over total expenditure, percentage of white people over the whole population, percentage of population with high school degree over the whole population, medium family income, property tax assessment, employment, population or population density, county dummy, and year dummies. Data is county level and collected through US Census Bureau. The data includes ninety-five counties in Tennessee for five years of 1962, 1972, 1982, 1992, and 2002 (see table 2 for data statistics summary). Also, the data is balanced except that in migration rate (per 100 persons) of the 67-plus cohort for 2002 cannot be obtained. 475 observations are used to be regressed for the first group of models and 380 observations are used to be regressed for the second group since data for 2002 has to be dropped for the second group. Stata software is applied to do the regression for the two groups of fixed-effect models. The results indicate that the elderly in-migration rate is positively correlated to the share of elderly people over the whole population, the rate of people with high school degree, medium family income, and population (or population density). Also, it is no difference in terms of the results either population or population density is used as one of the independent variables. County governors could make appropriate strategies or policies to pull those elderly in according to the results by improving amenities or life quality for elderly in each county. The weakness of this paper is that it is hard to test the endogeneity of independent variables because 1) there is no instrumental variables so that the hausman test result calculated from the difference between the original model and 2SLS cannot be conducted; and 2) it is hard to get all the factors out of the error term as explanatory variables and as a result, it is difficult not to allow correlation between the explanatory variables and unobserved factors in the error term.Elderly In-Migrants, Fixed-Effect Model, and Tennessee, Community/Rural/Urban Development,

Demand Analysis for Shrimp in the United States

This paper analyzes the demand for shrimp along with beef, pork, and chicken in the US food market, which contributes much to predicting supply strategies, consumer preferences and policy making. It focuses on the own and cross relationship between the expenditure share and price, income changes. An Almost Ideal Demand System (AIDs) model and two alternative specifications are used to estimate a system of expenditure share equations for shrimp, beef, pork, and chicken. Empirical results indicated that some insignificant slope coefficients and inappropriate signs of them did not comply with microeconomic theory. This could be caused by heteroscedasticity, autocorrelation, a limitation in the data used, or shrimp is a commodity that is quite different.expenditure share, own and cross relationship, Almost Ideal Demand System (AIDs), heteroscedasticity, and autocorrelation, Demand and Price Analysis,

Two classes of regulatory subunits coassemble in the same BK channel and independently regulate gating

High resolution proteomics increasingly reveals that most native ion channels are assembled in macromolecular complexes. However, whether different partners have additive or cooperative functional effects, or whether some combinations of proteins may preclude assembly of others are largely unexplored topics. The large conductance Ca(2+)-and-voltage activated potassium channel (BK) is well-suited to discern nuanced differences in regulation arising from combinations of subunits. Here we examine whether assembly of two different classes of regulatory proteins, β and γ, in BK channels is exclusive or independent. Our results show that both γ1 and up to four β2-subunits can coexist in the same functional BK complex, with the gating shift caused by β2-subunits largely additive with that produced by the γ1-subunit(s). The multiplicity of β:γ combinations that can participate in a BK complex therefore allow a range of BK channels with distinct functional properties tuned by the specific stoichiometry of the contributing subunits

Simplifying intensity-modulated radiotherapy plans with fewer beam angles for the treatment of oropharyngeal carcinoma.

The first aim of the present study was to investigate the feasibility of using fewer beam angles to improve delivery efficiency for the treatment of oropharyngeal cancer (OPC) with inverse-planned intensity-modulated radiation therapy (IP-IMRT). A secondary aim was to evaluate whether the simplified IP-IMRT plans could reduce the indirect radiation dose. The treatment plans for 5 consecutive OPC patients previously treated with a forward-planned IMRT (FP-IMRT) technique were selected as benchmarks for this study. The initial treatment goal for these patients was to deliver 70 Gy to > or = 95% of the planning gross tumor volume (PTV-70) and 59.4 Gy to > or = 95% of the planning clinical tumor volume (PTV-59.4) simultaneously. Each case was re-planned using IP-IMRT with multiple beam-angle arrangements, including four complex IP-IMRT plans using 7 or more beam angles, and one simple IMRT plan using 5 beam angles. The complex IP-IMRT plans and simple IP-IMRT plans were compared to each other and to the FPIMRT plans by analyzing the dose coverage of the target volumes, the plan homogeneity, the dose-volume histograms of critical structures, and the treatment delivery parameters including delivery time and the total number of monitor units (MUs). When comparing the plans, we found no significant difference between the complex IP-IMRT, simple IP-IMRT, and FP-IMRT plans for tumor target coverage (PTV-70: p = 0.56; PTV-59.4: p = 0.20). The plan homogeneity, measured by the mean percentage isodose, did not significantly differ between the IP-IMRT and FP-IMRT plans (p = 0.08), although we observed a trend toward greater inhomogeneity of dose in the simple IP-IMRT plans. All IP-IMRT plans either met or exceeded the quality of the FP-IMRT plans in terms of dose to adjacent critical structures, including the parotids, spinal cord, and brainstem. As compared with the complex IP-IMRT plans, the simple IP-IMRT plans significantly reduced the mean treatment time (maximum probability for four pairwise comparisons: p = 0.0003). In conclusion, our study demonstrates that, as compared with complex IP-IMRT, simple IP-IMRT can significantly improve treatment delivery efficiency while maintaining similar target coverage and sparing of critical structures. However, the improved efficiency does not significantly reduce the total number of MUs nor the indirect radiation dose

Knockout of the BK β2 subunit abolishes inactivation of BK currents in mouse adrenal chromaffin cells and results in slow-wave burst activity

Rat and mouse adrenal medullary chromaffin cells (CCs) express an inactivating BK current. This inactivation is thought to arise from the assembly of up to four β2 auxiliary subunits (encoded by the kcnmb2 gene) with a tetramer of pore-forming Slo1 α subunits. Although the physiological consequences of inactivation remain unclear, differences in depolarization-evoked firing among CCs have been proposed to arise from the ability of β2 subunits to shift the range of BK channel activation. To investigate the role of BK channels containing β2 subunits, we generated mice in which the gene encoding β2 was deleted (β2 knockout [KO]). Comparison of proteins from wild-type (WT) and β2 KO mice allowed unambiguous demonstration of the presence of β2 subunit in various tissues and its coassembly with the Slo1 α subunit. We compared current properties and cell firing properties of WT and β2 KO CCs in slices and found that β2 KO abolished inactivation, slowed action potential (AP) repolarization, and, during constant current injection, decreased AP firing. These results support the idea that the β2-mediated shift of the BK channel activation range affects repetitive firing and AP properties. Unexpectedly, CCs from β2 KO mice show an increased tendency toward spontaneous burst firing, suggesting that the particular properties of BK channels in the absence of β2 subunits may predispose to burst firing

Improving Case Definition of Crohnʼs Disease and Ulcerative Colitis in Electronic Medical Records Using Natural Language Processing

available in PMC 2014 June 01Background: Previous studies identifying patients with inflammatory bowel disease using administrative codes have yielded inconsistent results. Our objective was to develop a robust electronic medical record–based model for classification of inflammatory bowel disease leveraging the combination of codified data and information from clinical text notes using natural language processing. Methods: Using the electronic medical records of 2 large academic centers, we created data marts for Crohn’s disease (CD) and ulcerative colitis (UC) comprising patients with ≥1 International Classification of Diseases, 9th edition, code for each disease. We used codified (i.e., International Classification of Diseases, 9th edition codes, electronic prescriptions) and narrative data from clinical notes to develop our classification model. Model development and validation was performed in a training set of 600 randomly selected patients for each disease with medical record review as the gold standard. Logistic regression with the adaptive LASSO penalty was used to select informative variables. Results: We confirmed 399 CD cases (67%) in the CD training set and 378 UC cases (63%) in the UC training set. For both, a combined model including narrative and codified data had better accuracy (area under the curve for CD 0.95; UC 0.94) than models using only disease International Classification of Diseases, 9th edition codes (area under the curve 0.89 for CD; 0.86 for UC). Addition of natural language processing narrative terms to our final model resulted in classification of 6% to 12% more subjects with the same accuracy. Conclusions: Inclusion of narrative concepts identified using natural language processing improves the accuracy of electronic medical records case definition for CD and UC while simultaneously identifying more subjects compared with models using codified data alone.National Institutes of Health (U.S.) (NIH U54-LM008748)American Gastroenterological AssociationNational Institutes of Health (U.S.) (NIH K08 AR060257)Beth Isreal Deaconess Medical Center (Katherine Swan Ginsburg Fund)National Institutes of Health (U.S.) (NIH R01-AR056768)Burroughs Wellcome Fund (Career Award for Medical Scientists)National Institutes of Health (U.S.) (NIH U01-GM092691)National Institutes of Health (U.S.) (NIH R01-AR059648

Normalization of Plasma 25-Hydroxy Vitamin D Is Associated with Reduced Risk of Surgery in Crohn’s Disease

available in PMC 2014 August 01AB Background: Vitamin D may have an immunologic role in Crohn's disease (CD) and ulcerative colitis (UC). Retrospective studies suggested a weak association between vitamin D status and disease activity but have significant limitations. Methods: Using a multi-institution inflammatory bowel disease cohort, we identified all patients with CD and UC who had at least one measured plasma 25-hydroxy vitamin D (25(OH)D). Plasma 25(OH)D was considered sufficient at levels >=30 ng/mL. Logistic regression models adjusting for potential confounders were used to identify impact of measured plasma 25(OH)D on subsequent risk of inflammatory bowel disease-related surgery or hospitalization. In a subset of patients where multiple measures of 25(OH)D were available, we examined impact of normalization of vitamin D status on study outcomes. Results: Our study included 3217 patients (55% CD; mean age, 49 yr). The median lowest plasma 25(OH)D was 26 ng/mL (interquartile range, 17-35 ng/mL). In CD, on multivariable analysis, plasma 25(OH)D =30 ng/mL. Similar estimates were also seen for UC. Furthermore, patients with CD who had initial levels <30 ng/mL but subsequently normalized their 25(OH)D had a reduced likelihood of surgery (odds ratio, 0.56; 95% confidence interval, 0.32-0.98) compared with those who remained deficient. Conclusion: Low plasma 25(OH)D is associated with increased risk of surgery and hospitalizations in both CD and UC, and normalization of 25(OH)D status is associated with a reduction in the risk of CD-related surgery. (C) Crohn's & Colitis Foundation of America, Inc

Similar Risk of Depression and Anxiety Following Surgery or Hospitalization for Crohn's Disease and Ulcerative Colitis

OBJECTIVES: Psychiatric comorbidity is common in Crohn's disease (CD) and ulcerative colitis (UC). Inflammatory bowel disease (IBD)-related surgery or hospitalizations represent major events in the natural history of the disease. The objective of this study is to examine whether there is a difference in the risk of psychiatric comorbidity following surgery in CD and UC. METHODS: We used a multi-institution cohort of IBD patients without a diagnosis code for anxiety or depression preceding their IBD-related surgery or hospitalization. Demographic-, disease-, and treatment-related variables were retrieved. Multivariate logistic regression analysis was performed to individually identify risk factors for depression and anxiety. RESULTS: Our study included a total of 707 CD and 530 UC patients who underwent bowel resection surgery and did not have depression before surgery. The risk of depression 5 years after surgery was 16% and 11% in CD and UC patients, respectively. We found no difference in the risk of depression following surgery in the CD and UC patients (adjusted odds ratio, 1.11; 95% confidence interval, 0.84–1.47). Female gender, comorbidity, immunosuppressant use, perianal disease, stoma surgery, and early surgery within 3 years of care predicted depression after CD surgery; only the female gender and comorbidity predicted depression in UC patients. Only 12% of the CD cohort had ≥4 risk factors for depression, but among them nearly 44% subsequently received a diagnosis code for depression. CONCLUSIONS: IBD-related surgery or hospitalization is associated with a significant risk for depression and anxiety, with a similar magnitude of risk in both diseases.National Institutes of Health (U.S.) (U54-LM008748

Psychiatric co-morbidity is associated with increased risk of surgery in Crohn's disease

Psychiatric co-morbidity, in particular major depression and anxiety, is common in patients with Crohn's disease (CD) and ulcerative colitis (UC). Prior studies examining this may be confounded by the co-existence of functional bowel symptoms. Limited data exist examining an association between depression or anxiety and disease-specific endpoints such as bowel surgery.National Institutes of Health (U.S.) (NIH U54-LM008748)American Gastroenterological AssociationNational Institutes of Health (U.S.) (NIH K08 AR060257)Beth Isreal Deaconess Medical Center (Katherine Swan Ginsburg Fund)National Institutes of Health (U.S.) (NIH R01-AR056768)National Institutes of Health (U.S.) (NIH U01-GM092691)National Institutes of Health (U.S.) (NIH R01-AR059648)Burroughs Wellcome Fund (Career Award for Medical Scientists)National Institutes of Health (U.S.) (NIH K24 AR052403)National Institutes of Health (U.S.) (NIH P60 AR047782)National Institutes of Health (U.S.) (NIH R01 AR049880